discretionary

Altogether, discretionary spending accounted for around 25% of the total in the 2023 financial year according to the Congressional Budget Office, with more than half of that going to defence.

Yet if all of the $2 trillion in US government expenditure savings now being targeted by Musk were to come from discretionary spending, analysts calculate that entire agencies - from transport, to agriculture, to Homeland Security - would have to be entirely closed down.

Discretionary spending accounted for only $1.7 trillion in 2023.

In theory, discretionary spending would be easier for the incoming Trump administration to cut than mandatory spending.

After taking control of the House of Representatives in 2022, Republican lawmakers have struggled to pass legislation to deliver considerably smaller cuts of $130bn in discretionary government spending after meeting opposition from other Republicans.